Process for depositing Cr-bearing layer

Abstract

A method of applying a Cr-bearing layer to a substrate, comprises introducing an organometallic compound, in vapor or solid powder form entrained in a carrier gas to a plasma of an inductively coupled plasma torch or device to thermally decompose the organometallic compound and contacting the plasma and the substrate to be coated so as to deposit the Cr-bearing layer on the substrate. A metallic Cr, Cr alloy or Cr compound such as chromium oxide, nitride and carbide can be provided on the substrate. Typically, the organometallic compound is introduced to an inductively coupled plasma torch that is disposed in ambient air so to thermally decompose the organometallic compound in the plasma. The plasma is directed at the substrate to deposit the Cr-bearing layer or coating on the substrate.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A method of applying a chromium-bearing layer to at least a portion of a substrate, comprising introducing a chromium bearing organometallic compound in a carrier gas to an inductively coupled plasma to thermally decompose said organometallic compound, and communicating the plasma and the substrate to be coated so as to deposit a chromium-bearing layer on the substrate. 
     
     
       2. The method of claim 1 wherein the inductively coupled plasma is generated by an inductively coupled torch disposed in ambient air. 
     
     
       3. The method of claim 1 wherein said organometallic compound is introduced to the inductively coupled plasma as a vapor in an inert carrier gas. 
     
     
       4. The method of claim 1 wherein said organometallic compound is introduced to the inductively coupled plasma as solid powder entrained in an inert carrier gas. 
     
     
       5. The method of claim 1 wherein the chromium-bearing layer comprises metallic chromium. 
     
     
       6. The method of claim 5 wherein the organometallic compound comprises chromium carbonyl. 
     
     
       7. The method of claim 1 wherein the chromium-bearing layer comprises chromium oxide. 
     
     
       8. The method of claim 7 wherein the organometallic compound comprises chromium carbonyl. 
     
     
       9. The method of claim 1 wherein the chromium-bearing layer comprises chromium nitride. 
     
     
       10. The method of claim 9 wherein the organometallic compound comprises a chromium derivative of 1-dimethyl 1 amino -2,8,9-trimethyl-2,8,9-triaza-5-aza-tricyclo [3.3.0] undecane. 
     
     
       11. The method of claim 1 wherein the chromium-bearing layer comprises chromium carbide. 
     
     
       12. The method of claim 11 wherein the organometallic compound comprises tetramethyl chromium. 
     
     
       13. The method of claim 1 wherein the chromium-bearing layer comprises a chromium alloy with another metal. 
     
     
       14. The method of claim 13 further including an organometallic compound of said another metal.